Thermal delay switch



March 30, 1954 J BQNANNQ 2,673,909

THERMAL DELAY SWITCH Original Filed Nov, 12, 1947 Av-suLArzazQ a Z8 4 /f 5y /7 8 /0 INVENTOR.

A TTORNE Y Patented Mar. 30, 1954 Joseph L. Bonanno, Madison, N. .L,

' The Lionel'Corporation,

, .poration olNew York assignor to New York, N. Y., a cor- Original application November 12, 1947, Serial No. 785,407, now Patent No. May 6, 1952. Divided and this 2,595,919, dated application tober 8, 1951, Serial No. 250,342

2 Claims.

The present invention relates to thermal delay switches and is more particularly directed to ward such switches suitable for use in the operation of toy railroad cars.

It is customary to provide toy railroad cars with an instantaneously operated device such as an electromagnetically operated coupler and with some other electrically operated accessories such as dump car mechanism, door opening mechanism, mechandise handling mechanism or the like, operated less frequently, or subsequently. See, for example, my Patent No. 2,232,508, February 18, 1941. The present invention aims to provide an arrangement whereby the couplers may be actuated when desired and whereby the other accessories may be actuated after the couplers have been actuated, the controls requiring no more than the usual power and return rails which carry the propulsion current for the toy railroad trains.

According to the present invention, the car carries a relay which is not responsive to propulsion current but is responsive to non-propulsion current in the rails. This non-propulsion current may be a tuned radio, frequency current, produced as shown in myapplication, SerialNo. 779,273, filed October 11, 1947, now Patent No. 2,622,542, dated December 23, 1952, or a direct current component superimposed upon the A. C. propulsion current. A relay operated in such superposed current is shown in my Patent No. 2,155,343, dated April 18, 1939.

The thermal delay switch of the present invention makes it possible to control the couplers or the accessory as desired when the car is at any place along the usual two rail or three rail track.

Other and further objects will appear as the description proceeds.

The accompanying drawings show, for purposes of illustrating the present invention, one form of thermal delay switch, together with modified forms of circuit, it being understood that the drawings are illustrative of the invention rather than limiting the same.

In these figures:

Figure 1 is a perspective view of a thermal delay switch together with wiring diagram;

Figure 2 is a cross-sectional view on the line 2-2 of Figure 1;

Figure 3 is an end view taken from the right of Figure 2 Figure 4 is an exploded view showing the component parts; and

Figure 5 illustrates a modified wiring diagram.

The thermal delay switch has an insulating base l0 having a threaded hole two notches I2, I 2. and two holes l3, l3. Immediately above this base is a bimetallic thermal element l5 of U-shape. This thermal element has two contact terminals l8, H which protrude beyond the base, two holes |8, |8 spaced the same as the holes l3, l3, and its left end as shown in the drawings is entirely free. This bimetallic element is so arranged that its free end bends upwardly away from the base upon heating of the bimetallic element by currents flowing through it.

Immediately above the bimetallic element I5 is aspacer l9, made of insulating material and above this spacer is a sheet of insulating paper and a flexible sheet metal contact plate 2|. The contact plate, insulating sheet and. thermal element all have the same general contour and are provided with holes which align with the holes I3. The free end of the contact plate 2| carries a silver contact 24. Immediately above the contact plate 2| is another spacer similar to the spacer IS. A cover plate 26 has stiffening side flanges 21, 21 and prongs 28 adapted to enter the notches l2 and be bent about the bottom of the base. The plate 26 has holes 29 adapted to be aligned with similar plate holes in the other parts, and hollow rivets 3|, 3| and insulated spacers 30, 30 are employed to assemble the other parts together. The contact plate 26 has a bendable tongue 32 carrying a silver contact 33 opposite the contact 24 of the flexible plate 2|. The tongue 32 is adapted to be bent to adjusted posi tion by a screw 34 passing through the threaded hole The contact plate 2| has a protruding soldering lug 35 and the cover member 25 has a similar lug 36. The thermal delay switch is carried on the car and one side of the bimetallic element (for example I1) is connected by wires 31, 38 with electromagnetic couplers 39, 39 carried by the car and grounded as usual to the return rail 45. The other terminal I6 01' the bimetallic element is connected by wire 40 with a contact 4| adapted to be engaged by an armature 42 of a relay 43. As shown in Figure 1, this relay, shown in Patent 2,526,453, is of the type adapted for use with an electronic controller. The relay is connected to the power rail 44 and grounded rail 45 through a rectifier 46 and turned receiver 41.

- When the track circuit is provided with radio frequency currents of the frequency corresponding-with that of the tuned recei' he relay is actuated and current flows throug J he thermal element to the couplers to operatethem. On

heating of the thermal element it moves against the insulating sheet 20 and applies pressure to the free end of the flexible sheet 20 and applies pressure to the free end of the flexible contact plate 2i bringing the contact 24 against the contact 33. This interconnects plates 2| and 26. These plates may be employed as control switches for additional accessories. The circuit can be connected as shown in Figure 1 wherein t fi. 2elay connected side it of the thermal element is connected to one of the soldering lugs 35 or 35 while the other lug is connected to an accessory device such as an unloading coil 50, which is grounded. It will be noted in this arrangement that the current for operating the unloading coil does not pass through the thermal element. These parts can readily be manufactured and adjusted so as to operate with rather precise timing so that when the relay receives but a short impulse of operating current the couplers only are operated and when the relay circuit is closed for a few seconds. the thermal element acts to close the circuit to the other accessory.

The same structure for thermal retarder can be used as a direct thermal relay as indicated in if Figure 5 in which the thermal element I5; is in a circuit entirely difierent from that of contact members 24 and 33.

This application is a division of my application, Serial No. 785,407, filed November 12, 1947-, now Patent No. 2,595,919, dated May 6, 1952.

Since it is obvious that the invention may be embodied in other forms and constructions within the scope of the claims, I wish it to be understood that the particular form shown is but one of these forms, and various modifications and changes being possible, I do not otherwise limit myself in any way with respectthereto.

What is claimed is:

i. A thermal retarding switch comprising an insulating base plate, a U-shaped bimetallic thermal element overlying the base and having terminals extending from the ends of said thermal element, an insulating spacer on the ends oi said thermal element, a flexible conducting plate on the spacer and having an end spaced from the thermal element and carrying insulation in its lower face opposite the thermal element, an insulating spacer on the conducting plate, a metallic cover plate above the second spacer and normally out of-jcontact with the flexible plate, but engageable' thereby upon heating of the thermal element to bend the flexible plate, and means to clamp the parts together, maintaining said thermal element, conducting plate and cover plate electrically insulated from each other.

2. In. a thermal retarder, an insulating base plate, a cover plate parallel therewith and spaced therefrom, the cover plate having an adjustable contact adjacent one. end and a wiring terminal, a fiat U-shaped' bimetallic thermal element adjacent the base with the center of the U opposite the adjustable contact, two insulating spacers, one above the ends of the thermal element, the other below the cover plate and above the first, a flexible contact plate and an insulating sheet between the spacers and extending between the thermal element and the cover with the contact plate above the insulating sheet, and below the adjustable contact, means to secure the cover plate, spacers, flexible plate, insulating sheet, thermal element and base together at the open end of the U-shaped thermal element, maintaining said thermal element, contact plate and cover plate electrically insulated from each other, with the free end of the flexible contact plate normally out of contact with the adjustable contact but engageable therewith upon heating of the thermal element, and a base carried screw bearing against said cover plate for shifting said adjustable contact.

, JOSEPH L. BQNANNO.

References Cited in the file of this patent UNITED STATES PATENTS 

